package com.xiaoyu.algorithmimpl;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.channels.Channel;
import java.nio.channels.FileChannel;

public class FileReadImpl {
	public static void nioTransferCopy(File source, File target) {
		FileChannel in = null;
		FileChannel out = null;
		FileInputStream inStream = null;
		FileOutputStream outStream = null;
		try {
			inStream = new FileInputStream(source);
			outStream = new FileOutputStream(target);
			in = inStream.getChannel();
			out = outStream.getChannel();
			in.transferTo(0L, in.size(), out);
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			close(inStream);
			close(in);
			close(outStream);
			close(out);
		}
	}

	@SuppressWarnings("unused")
	private static void nioBufferCopy(File source, File target) {
		FileChannel in = null;
		FileChannel out = null;
		FileInputStream inStream = null;
		FileOutputStream outStream = null;
		try {
			inStream = new FileInputStream(source);
			outStream = new FileOutputStream(target);
			in = inStream.getChannel();
			out = outStream.getChannel();
			ByteBuffer buffer = ByteBuffer.allocate(4096);
			while (in.read(buffer) != -1) {
				buffer.flip();
				out.write(buffer);
				buffer.clear();
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			close(inStream);
			close(in);
			close(outStream);
			close(out);
		}
	}

	public static void customBufferBufferedStreamCopy(File source, File target) {
		InputStream fis = null;
		OutputStream fos = null;
		try {
			fis = new BufferedInputStream(new FileInputStream(source));
			fos = new BufferedOutputStream(new FileOutputStream(target));
			byte[] buf = new byte[4096];
			int i;
			while ((i = fis.read(buf)) != -1) {
				fos.write(buf, 0, i);
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			close(fis);
			close(fos);
		}
	}

	public static void customBufferStreamCopy(File source, File target) {
		InputStream fis = null;
		OutputStream fos = null;
		try {
			fis = new FileInputStream(source);
			fos = new FileOutputStream(target);
			byte[] buf = new byte[4096];
			int i;
			while ((i = fis.read(buf)) != -1) {
				fos.write(buf, 0, i);
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			close(fis);
			close(fos);
		}
	}

	private static void close(InputStream in) {
		try {
			in.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	private static void close(OutputStream out) {
		try {
			out.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	private static void close(Channel channel) {
		try {
			channel.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}